Production of organo-halides



United States Patent grnla No Drawing. Filed Nov. 14, 1963, Ser. No. 323,600

6 Claims. (Cl. 260-652) t:

This invention relates in general to organo-halides and in particular to a novel process for the production of organo-halides by the reaction of organo-metal-containing compounds with a halogen.

In US Patent 2,935,536 there is described a process for the production of organo-halides in which recovery of the desired product is described as being facilitated by the use of a complexing agent such as pyridine, whose purpose is to combine with the metal halides so as to leave the metal halides no longer free to act upon the organo-halides. Many varieties and wide ranges of metals, halides, complexing agents, solvents or diluents and organo radicals are set forth in that patent.

The yields of the process of the foregoing patent are disappointingly low however, being in the region of 70 to 76 percent. It is desirable, therefore, to find a way whereby yields may be improved without sacrificing certain desirable aspects of that foregoing invention.

It is accordingly an object of the present invention to provide improved yields of organo-halides in the reaction of halogens with organo-metals, organo metal halides and organo metal hydrides.

Another object of the present invention is to provide improved reaction conditions for the halogenation of organo-metal compounds as a result of which improved yields of organo-halides are possible.

Other and further objects and features of the present invention will become apparent upon a careful consideration of the following specification.

In accordance with the basic teachings of the present invention, an improved process for the halogenation of organo-metal compounds in the presence of a complexing agent such as pyridine is provided. As the term organometal compound is used, it refers to compounds of the formula as set forth in the foregoing patent, wherein R is a hydrocarbon radical, Me is a metal selected from the class consisting of aluminum, antimony, bismuth, cadmium, copper, gallium, germanium, indium, lead, mercury, thallium, tin and zinc, with the group identified by X including hydrogen and halogens with a subscript n which is not greater than the subscript m, the sum of m and n totalling the valency of Me, of which n but not in may be zero. This improved process provides yields in the region of 90 percent as contrasted to the 70-76 percent yields provided by the process of the prior art. The improvement resides principally in the performance of the prior art process in complete darkness, which provides not merely a higher yield, but a far higher quality product and a remarkable degree of freedom from the production of undesirable components, principally higher order chlorides and paraflins produced by side reactions. Such undesirable components encountered in halogenation without the exclusion of light generally impart undesired properties such as coloration and are not as easily removed as might be desired.

The exclusion of light from the reactions under consideration has application to the broad categories or classes of reactant, diluents or solvents, and complexing agents set forth in the above identified patent. The yields of 70-76 percent reported in that patent have in general been substantially duplicated in experimentation without Patented Nov. 1, 1966 ICC the exclusion of light and have been improved substantially by the exclusion of light.

The substantial increase in yield to approximately 90 percent when the reaction is performed with the exclusion of light is of major commercial importance since it represents virtually a threefold reduction in impurities that must be removed from the product. This improvement is not altogether a cost-free or inconvenience-free proposition, because it does not permit the unrestricted inclusion of viewing windows, liquid level sight glasses, closed circuit television or the like, normally used or desired in such installations but at least it does not involve additional process steps nor add cost items for additional new materials.

Example I A 200 ml. 3-neck flask was fitted with a thermometer, dropping funnel, nitrogen atmosphere, magnetic stirrer and a tube with delivery system for supplying chlorine. A quantity of 150 parts by weight of carbon tetrachloride was placed in the flask and 4.2 parts of pyridine was added. To this was added with stirring during one hour 20 parts of tri-n-octylaluminum. A temperature of 14 18 C. was maintained. During the next 2.5 hours, 12 parts of chlorine was introduced and a temperature of 1824 C. maintained. The mixture was hydrolyzed with water, then with hydrochloric acid. Analysis recorded a 71 percent yield of alkyl chloride.

Example [I The foregoing experiment was repeated with reaction temperature of 15 to -10 C. instead of 14 to 18 C., to provide a yield of 69 percent alkyl chloride.

Example 111 The apparatus was set up as in Example I. A quantity of 75 parts of carbon tetrachloride was placed in the flask and 2.5 parts of pyridine was added. To this was added during one hour with stirring and at a temperature of 15 C., a quantity of 10 parts of tri-n-octylaluminum. The flask was completely covered with several layers of aluminum foil to exclude light and 6.0 parts of chlorine was added during one hour maintaining stirring and a temperature of 10l6 C. The mixture was hydrolyzed and a yield of percent alkyl halide was obtained.

Example IV The apparatus is set up and materials proportioned as in Example HI with 12 parts of bromine substituted for the chlorine and added through the dropping funnel slowly with stirring. The product is n-octyl bromide, a liquid at the reaction temperature.

Example V Same as Example III with 5 parts of tripropylamine substituted for the pyridine.

Example VI Same as Example III with parts pyridine substituted for the carbon tetrachloride.

Example VII Same as Example III with 7.0 parts of triphenylaluminum substituted for tri-n-octylaluminum. The product is chlorobenzene.

Example VIII Same as Example 111 with 12 parts of tetra-o-toluylgermanium substituted for tri-n-octylaluminu-m. The product is orthochlorotoluene, a color-less liquid at the reaction temperature.

3 Example IX Same as Example III with 9.2 parts triethylgermanium bromide substituted for tri-n-octylaluminum. The product is ethyl chloride.

Example X Same as Example In with 12 parts of triphenylgermanium hydride substituted for tri-n-octylaluminum. The product "is chloro benzene.

Example XI Same as Example III with 15 parts dibenzyl mercury substituted for tri-n-octylaluminum and 40 parts benzene substituted for carbon tetrachloride. The product is ben zyl chloride.

Example XII Same as Example III with 100 parts pentachloro ethane substituted for carbon tetrachloride.

Example XIII Same as Example III with 75 parts ethylene dichloride substituted for carbon tetrachloride.

Example XIV Same as Example III with 5.0 parts quinoline substituted for pyridine.

Example XV Following the procedure of Example IH, various hydrocarbon halides are produced as noted hereinbelow. Thus, by utilizing:

(a) Tri-n-hexyl aluminum and chloride to form n-hexyl chloride, a colorles liquid having a boiling point of about 132 C.;

(b) Tri-n-hexyl aluminum and bromine to form n-hexyl bromide, a colorless liquid having a boiling point 06E 156- C.;

(c) Tri-n-hepty-l aluminum and chlorine to form n-heptyl chloride, a colorless liquid having a boiling p'oint of 159 C.;

(d) Tri-n-heptyl aluminum and bromine to form n'heptyl bromide, a colorless liquid having a boiling point of 179 C.;

(e) Tri-n-decyl aluminum and iodine to form n-decyl iodide, a liquid having a boiling point of 132 C. at mm. pressure;

(f) Tri-n-dodecyl aluminum and bromine to form n-dodecyl bromide, a liquid having a boiling point of 17580 C. at 45 mm. pressure, and commonly known as lauryl bromide;

(g) Tri-n-hexadecyl aluminum and iodine to form nhexadecyl iodide, a plate-like crystalline solid having a melting point of 22 C. and a boiling point of 211 C. at 15 mm. pressure and commonly known as cetyl iodide;

(h) Tri-n-hexacosyl aluminum and bromine to form n-hexacesyl bromide, commonly known as ceryl bromide;

(i) Tri-n-tetracontyl aluminum and bromide to form tetracontyl bromide, or n-C H Br;

(j) Tristyryl aluminum and chlorine to form styryl chloride or ohlorophenylet-hylene, a liquid having a boiling point of about 139 C.;

(k) Triphenyl aluminum and bromine to form phenyl bromide, a colorless oily liquid having a boiling point of about 155 C.;

(l) Tetracyclohexyl tin and chlorine to form cyclohexyl chloride, a colorless liquid having a boiling point of about 143 C.

Example XVI While experience to date has indicated that the hydrocarbon aluminums are preferable starting hydrocarbon metals for the purpose of this invention, any of the known hydrocarbon metals may be employed in carrying out the process of this invention. Thus, there may be employed:

(1) Penta-n-butyl antimony and chlorine to form n-butyl chloride;

(2) Penta-ethyl bismuth and bromine to form ethyl bromide;

(3) Di-isoamyl cadmium and iodine to form isoamyliodide;

(4) Tetra-n-hexyl germanium and bromine to form n-hexyl bromide;

(5) Tetra-isobutyl lead and chlorine to form isobutyl chloride;

(6) Di-hexyl mercury and bromine to form n-hexyl bromide;

(7) Tri-ethyl gallium and iodine to form ethyl iodide;

(8) Tetra-isobutyl indium and chlorine to form isobutyl chloride;

(9) Tri-isobutyl antimony and bromine to form isobutyl bromide;

(10) Tri-n-amyl tin and bromine to form n-amyl bromide;

(l1) Di-isobutyl zinc and chlorine to form isobutyl chloride.

From the foregoing it is obvious that the present invention has broad application to the halogenation of organemetal compounds to provide improved yields, higher quality of product and reduced product recovery costs.

What is claimed is:

1. The process of manufacturing an organo halide by the reaction with a halogen selected from the group con sisting of chlorine, bromine and iodine of an organo-metal compound ofthe formula R MeX wherein R is a hydrocarbon radical, Me is a metal selected from the class consisting of aluminum, antimony, bismuth, cadmium, copper, gallium, germanium, indium, lead, mercury, thalium, tin and zinc,.X is one of a group including halogens selected from the group consisting of chlorine, bromine and iodine and hydrogen, and m and n are numbers whose sum totals the valency of Me and of which n but not m may be zero, which process comprises gradually adding an organo-metal compound as above defined to a liquid mixture of an inert organic solvent and a complexing chemical selected from the class consisting of the tertiary alkyl amines, the azines, the alkyl azines land the haloazines while agitating and cooling the resulting liquid mixture to a temperature ranging from about 15 C. to 30 C. to remove the exothermically generated heat therefrom, then adding a halogen selected from the group consisting of chlorine, bromine and iodine slowly to said liquid mixture with the exclusion of light, while continuing the cooling, at such a rate as to maintain the liquid mixture at a temperature ranging from about 15 C. to 30 C., whereby the halogen added reacts with the organo-metal to produce an organ c-halide and a metal halide, the latter reacting as it is formed with the said complexing chemical to produce a metal halide complex which is not reactive with the organo-metal or the organo-halide,.and recovering the organo-halide from the liquid mixture.

2. The process defined in claim 2 wherein the organometal is tIi-n-octylaluminum, the organic solvent is carbon tetrachloride the complexing chemical is pyridine, and the halogen is chlorine.

3. A process for the manufacture of a hydrocarbon halide by reaction of a hydrocarbon aluminum with a halogen selected from the group consisting of chlorine, bromine and iodine which comprises adding gradually to a liquid mixture of an inert organic solvent and a complexing chemical selected from the class consisting of the tertiary alkylamines, the azines, the alkyl-azines and the halo-azines, a hydrocarbon aluminum of the formula R AlX in which R is a hydrocarbon radical having from 2 to 40 carbon atoms, X is one of a group including halogens selected from the group consisting of chlorine, bromine and iodine and hydrogen, and m and n are digits the sum of which totals three and of which n but not m may be zero, agitating and cooling said liquid mixture during the said addition to a temperature ranging from about 15 C. to 30 C. to remove exothermically generated heat therefrom, then adding a halogen selected from the group consisting of chlorine, bromine and iodine slowly to said liquid mixture with the exclusion of light, while continuing the agitation and cooling, at such a rate as maintain the resulting liquid mixture at a temperature lower than 30 C., whereby the halogen added reacts with the hydrocarbon aluminum to produce a hydrocarbon halide and an aluminum halide, the latter reacting as it is formed with the 'complexing chemical to produce an aluminum halide complex which is non-reactive with the hydrocarbon halide, and recovering the hydrocarbon halide from the resulting liquid mixture.

4. The process defined in claim 3 wherein the complexin g chemical is pyridine.

5. The process defined in claim 3 wherein the complexing chemical is quinoline.

6. The process defined in claim 3 wherein the hydrocarbon metal is trialkylaluminum, the solvent is carbon tetrachloride, the complexing chemical is pyridine and the halogen is chlorine.

References Cited by the Examiner LEON ZlTVER, Primary Examiner.

K. V. ROCKEY, Assistant Examiner. 

1. THE PROCESS OF MANUFACTURING AN ORGANANO-HALIDE BYE THE REACTION WITH A HALOGEN SELECTED FROM THE GROUP CONSISTING OF CHLORINE, BROMINE AND IODINE OF AN ORGANO-METAL COMPOUND OF THE FORMULA RM-ME-XN,WHEREIN R IS A HYDROCARBON RADICAL, ME IS A METAL SELECTED FROM THE CLASS CONSISTING OF ALUMINUM, ANTIMONY, BISMUTH, CADMIUM, COPPER, GALLIUM, GERMANIUM, INDIUM, LEAD, MERCURY, THALIUM, TIN AND ZINC, X IS ONE OF A GROUP INCLUDING HALOGENS SELECTED FROM THE GROUP CONSISTING OF CHLORINE, BROMINE AND IODINE AND HYDROGEN, AND M AND N ARE NUMBERS WHOSE SUM TOTALS THE VALENCY OF ME AND OF WHICH N BUT NOT M MAY BE ZERO, WHICH PROCESS COMPRISES GRADUALLY ADDING AN ORGANO-METAL COMPOUND AS ABOVE DEFINED TO A LIQUID MIXTURE OF AN INERT ORGANIC SOLVENT AND A COMPLEXING CHEMICAL SELECTED FROM THE CLASS CONSISTING OF THE TERTIARY ALKYL AMINES, THE AZINES, THE ALKYL-AZINES AND THE HALOAZINES WHILE AGITATING AND COOLING THE RESULTING LIQUID MIXTURE TO A TEMPERATURE RANGING FROM ABOUT 15*C. TO 30*C. TO REMOVE THE EXOTHERMICALLY GENERATED HEAT THEREFROM, THEN ADDING A HALOGEN SELECTED FROM THE GROUP CONSISTING OF CHLORINE, BROMINE AND IODINE SLOWLY TO SAID LIQUID MIXTURE WITH THE EXCLUSION OF LIGHT, WHILE CONTINUING THE COOLING, AT SUCH A RATE AS TO MAINTAIN THE LIQUID MIXTURE AT A TEMPERATURE RANGING FROM ABOUT 15*C. TO 30*C. WHEREBY THE HALOGEN ADDED REACTS WITH THE ORGANO-METAL TO PRODUCE AN ORGANO-HALIDE AND A METAL HALIDE, THE LATTER REACTING AS IT IS FORMED WITH THE SAID COMPLEXING CHEMICAL TO PRODUCE A METAL HALIDE COMPLEX WHICH IS NOT REACTIVE WITH THE ORGANO-METAL OR THE ORGANO-HALIDE, AND RECOVERING THE ORGANO-HALIDE FROM THE LIQUID MIXTURE. 